Transcript Managing Recordings of Interviews and Focus Groups

Making, Managing and Analysing
Recordings of Interviews and
Focus Groups
Duncan Branley
Goldsmiths’ College, University of London
20 January 2005
[email protected]
Contents
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What do you want to do with your recordings?
Recording and working with sound.
Equipment for interviews and focus groups.
Transferring your recordings onto computer.
Improving your recordings.
Transcribing.
Moving transcriptions to NVivo.
Automatically coding for turn-takers in NVivo.
What do you want to do with your
recordings?
• In-depth, qualitative exploration - longer term.
• Overview for commissioned research – short
timeframe.
• Archiving – formats and metadata.
• Publishing on CD or the web
• Quality – broadcast v research interviews.
What is sound?
• Energy felt as vibrations.
• Converted to electrical signal.
• Heard or recorded.
• Frequency – Pitch
• Hertz (Hz) and kiloHertz (kHz)
– waves/second.
• Amplitude – volume
• Human ear hears:
• Range 16Hz - 20kHz
• Range of normal speech 250Hz
– 8kHz
• Recorder’s frequency
response
(Images source:
www.howstuffworks.com)
Analogue & Digital Recording
• Analogue – exact replica -
magnetic
• Digital takes snapshots or
‘samples’
• Sampling rate/second
• Sampling precision or
resolution
• Each block is one sample
• Higher values match sound
wave better
• Channels: number of
signals
(Images source:
www.howstuffworks.com)
Digital Recording and File Size
• How many samples in 1 second?
• CD: 44,100 – upper hearing range 20,000 Hz
• Sampling precision:
• 8 bit (256 possible values) or 16 bit (65,536)
• 8 bits = 1 byte, 16 bits = 2 bytes
• Channels: monaural (mono) or stereo
• 1 minute of stereo sound at CD quality:
• 44,100 samples/channel/second x 2 bytes/sample x 60
seconds x 2 channels = 10,584,000 bytes = 10,336 KB =
10.1 MB
• mp3 and RealAudio – compression 1/10 – 1/14
Recording and Working with Sound
• Sound converted:
• From analogue to digital to record (ADC)
• From digital to analogue to play (DAC)
• Compressing digital audio files saves space:
• Uncompressed: WAV (PC), AIFF (Mac)
• Compressed:
• Space: double highest frequency of source:
• Speech: 250 Hz - 8,000 Hz =>16,000 or 22,050
• Telephone: 400 Hz - 3,400 Hz => 8,000
• See “Ready Reckoner”
Analogue and Digital Audio Compared
• Sound quality
• Not necessarily better – depends on sampling rate
• Main problem with analogue recordings: hiss
• Copies
• Each analogue copy degrades, digital doesn’t.
Unless compress already compressed file.
• Confidentiality – blanking identifiers
• Storage
• Media degradation v file format obsolescence
Recording Equipment (1)
• Practice beforehand – only one go at interview
• If disaster, write details of research encounter asap
• Consumer products v professional
• Easily replaceable supplies
• Ubiquity may reduce alienation
• ALL equipment should have:
• Recording indicator
• Ability to pause and resume easily
• Mike-in connection
• Line-in may not produce loud enough signal
Recording Equipment (2)
• Cassette recorders
• use at least Chrome CrO2 tape.
• turning tape may be a distraction, but longer = lower quality
• Dictaphones
• Convenient but not too good quality – often mono
• Minidisc
• Longer recording time 74-80 mins + LP
• Better quality recording – less mechanical noise
• Microphone
• External usually produces better results
• Best if a microphone-in connection – if just line-in may not produce
loud enough signal.
• Lead rather than direct plug-in – lessens machine noise.
Preparing Before you Arrive
• Check batteries or other power supply – and
carry spares
• Have spare media – unwrapped and labelled
• Have a checklist of how to use the recorder
• Carry the instruction book
• Cassette recorders and dictaphones
• Wind to beginning of recordable section
Preparing the Recording Environment
• Sound from speaker – moves in all directions
• Hard surfaces reflect – delay > echo
• Soft furnishings, smaller room and in corner
• Background noise
• Ambient noise in room
• Outside intrusions
• You and your participants – moving, eating
• Microphone
• Position as close to interviewees as possible – best 30 cm – 1 m
• If focus group, place in middle to pick up all sounds – stereo useful
• Place on stand – naturalises, but beware vibrations
• Check the recording level – although you may not be able to
• This will amplify the signal from the microphone
Recording Telephone Interviews
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Same advice – but some extra issues
Permission to record – ethical and legal
‘Thinner’ recorded sound – frequencies 400 - 3,400 Hz only
Could record from handset/speaker, but not good quality.
Rather – RJ-11 connector –
• As easy as connecting a computer to a modem
• Position between telephone and handset – balanced signal
• Telephone and line > your voice louder
• Also may not work with advanced systems
• Then connect recorder
• Might want a Y splitter too – to use two recorders
During Interviews and Focus Groups
• Concentrate on the interview!
• Monitor the recorder from time to time to
ensure that it’s still working.
After Interviews and Focus Groups
• Don’t stop recording until interview is really finished
• You may get some really interesting material towards the end
• When finished prevent over-writing by disabling media
• Minidiscs – slide the tab
• Cassettes – click the tabs out
• Label the recordings so that you know what’s on them later
• May want to label using a system to preserve anonymity
• Work it out in advance
Transferring your Recordings onto
Computer
• Connections: what’s making and what’s recording the
sound?
• Source: Line-out or Headphones/Speakers
• PC soundcard: Line-in or Microphone
• Set up sources using Windows Play Control
• Set volume level on sound source.
• Start recording on sound recording software
• Audacity free to download and use.
• May have own with eg soundcard or CD drive
• Then start playing the source.
• When play finished stop recording.
Connections
(Images source: http://geraldtomyn.tripod.com/digan.htm)
• Miniplug cable – 1/8 inch or 3.5 mm stereo (two rings) jack at
each end
• Carries Analogue only.
• Source: Line-out or Headphones/Speakers
• PC soundcard: Line-in (arrow into curves) or Microphone
• Connect speakers to PC soundcard line-out to monitor sound.
Windows Volume and Recording
Controls
• If you’re not getting any sound this is the first thing to check
• click on the volume button on the Windows toolbar
• Recording: you can only have one source selected at a time.
• The volume on both sides affects the loudness of the soundfile
• If it is too loud, it will distort; too quiet, you won’t hear it. Test it.
Recording with Audacity
1. Start Audacity – creates a new ‘project’
2. File | Preferences
1. Audio I/O – make sure it’s the same as the Volume controls – probably
your soundcard’s name.
2. Quality: Sample rate: 22,050 Hz format: 16 bit – don’t need CD
quality
3. File format: WAV (Microsoft 16 bit)
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File | Save As – give it a name
Click the circular red record button
Start playing the source
When finished click the yellow square stop button
File | Save
To use in other programs you need to export the file
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File | Export as either WAV (full quality) or mp3 (slightly lower, but
smaller file size).
Improving your Recordings in
Audacity
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Have created a WAV (PC) or AIFF (Mac) file.
Keep as original – work with a copy.
Could compress: mp3 – fine for speech.
Can work with parts of file (drag to select):
• Make quiet parts louder.
Effect | Amplify – accept default suggestion
• Blank identifying information (possibly after transcription)
Click on silence button (wave with flat line in middle).
• Remove hiss – find hiss with no words – be careful
Effect | Noise Removal – 2 steps
• Save brief extracts as separate files
• File | Export extract as…
• Remember to save your copy file.
Transcribing
• Do you need complete transcriptions?
• Summaries in Word or NVivo (with labelled proxy
document) – partial transcription.
• Useful first step – in field and for familiarisation
• Transcribe cassettes in full: foot-pedal control or
auto-rewind
• Use Transcriber to tie your transcription to the sound
files clause by clause – cp sub-titles.
• Can export to NVivo or a webpage.
• Transcription not neutral – part of your analysis.
Transcriber
• This enables you to create your transcriptions while following
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your sound files on screen.
Start Transcriber and open an audio file – WAV or mp3
Click on the play button and you’ll hear it.
When there’s a pause, press Enter and you’ll create a ‘segment
break’
When finished select Signal | Playback Mode | Loop on
Segment – this enables you to replay each segment while
you’re transcribing it. Press Tab to stop and start it and the up
and down arrows to move between segments.
When finished set back to continuous playback.
To create a new speaker: Segmentation | Create turn or Crtl-T
You can double click to enter the full identifier.
When finished save – and can export to html or NVivo format.
Moving Transcriptions to NVivo
• From Transcriber
• Must ensure have NVivoTxt.tcl installed in
C:\Program Files\DGA & LDC\Transcriber\converter
• File | Export | Export to NVivo Plain Text format.
• This will create a plain text file with the same name as the
soundfile you are working on – except with a .txt ending.
• In NVivo Create a new document by importing this
file – using the 'Read marked-up title and description
paragraphs' option.
Automatically Coding in NVivo
• Document formatted with Heading styles.
• NVivo can see structure.
• NVivo can use this to code for each turn-taker.
• Can use for structured, semi-structured and
unstructured interviews.
More Information
• Duncan Branley (2004) ‘Making and
Managing Audio Recordings’ in Clive Seale
(ed) Researching Society and Culture (2nd
edition): Sage, London pp 207-228.
• If you have further questions, email
[email protected]